Seasonality of manic depressive illness in Canada

Psychiatric hospitalizations for affective disorders in Warsaw, Poland: Effect of season and intensity of sunlight

“…In regard to mixed episode patients (mixed mania), unlike previous studies (Whitney et al, 1999;Cassidy and Carroll, 2002;Lee et al, 2007), we observed admission peaks during winter and late spring. These results could pave the way for a further investigation into this subject.…”

“…The authors usually combine this group of diagnosis with mania. However, the results point to a peak of such admissions during the summer months (Whitney et al, 1999;Cassidy and Carroll, 2002), as well as in early spring (Lee et al, 2007). Also, different patterns of seasonality of admissions depending on the sex of bipolar patients have been reported (Kerr-Correa et al, 1998;Hallam et al, 2006).…”

Evidence for Seasonal Mania

“…However, a study by Hare and Walter found that this assumption was not true; in that study, they found that both mania and schizophrenia had significant seasonality, with both peaking in summer. 37 Hence, only two studies that used hospital admission data to assess the seasonal pattern of mania (Whitney et al 1999 33 and Jain et al 1992 36 ) did not find any significant seasonality. , Although the Whitney et al study, which used hospital admission records in a 75-year study in the Ontario Provincial Psychiatric Hospital, 33 did not find any significant seasonal patterns for mania, they did find that mixed episodes peaked around summer.…”

“…37 Hence, only two studies that used hospital admission data to assess the seasonal pattern of mania (Whitney et al 1999 33 and Jain et al 1992 36 ) did not find any significant seasonality. , Although the Whitney et al study, which used hospital admission records in a 75-year study in the Ontario Provincial Psychiatric Hospital, 33 did not find any significant seasonal patterns for mania, they did find that mixed episodes peaked around summer. The discrepancies between the evidence in Tables 1 and 2 are apparent, given the fact that mania occurs in a heterogeneous group of disorders (e.g., bipolar disorder, medication-or substance-induced mood disorders, in association with some general medical conditions), and presentations vary even in the same individual.…”

Treatment of seasonal affective disorder: Unipolar versus bipolar differences

“…Several observational studies found spring and summer peak onset of mania in patients with bipolar illness, although some negative results have been reported [29][30][31][32][33]. It is possible that these findings are associated with the duration or rate of change of the photoperiod at that time of year, or with the amount of sunshine and sunlight radiation [31,34,35].…”